As a display device having high definition and low power consumption is required, various display devices such as a liquid crystal display device and an electroluminescent display device have been developed.
The electroluminescent display device has been spotlighted as a next generation display device due to excellent characteristics such as low light emission, low power consumption, and high definition, and the like, as compared with the liquid crystal display device.
There are an organic light emitting display device and an inorganic light emitting display device in an electric field display device. That is, an electric field display device may be classified into the organic light emitting display device and the inorganic light emitting display device according to a material of a light emitting layer.
Of these, the organic light emitting display device has received attention because the organic light emitting display device has a wide viewing angle, has a fast response speed, and is required to have low power consumption.
An organic material constituting such a light emitting layer may be formed to have a pattern for forming a pixel on a substrate by a fine metal mask method.
At this point, the fine metal mask, that is, a mask for deposition may have a through-hole corresponding to the pattern to be formed on the substrate, and, patterns of red (R), green (G), and blue (B) forming a pixel may be formed by depositing the organic material after the fine metal mask is aligned on the substrate.
Recently, a display device with ultra high definition (UHD) is required in various electronic devices such as virtual reality (VR) devices. Accordingly, a fine metal mask having fine sized through-holes capable of forming a pattern of UHD class is required.
A plurality of through-holes may be formed at a metal plate capable of being used as a deposition mask by an etching process.
At this point, when the plurality of through-holes are not uniform, uniformity of the deposition may be deteriorated, and as deposition efficiency of a pattern which is formed by the same, may be deteriorated, process efficiency may be deteriorated
Meanwhile, it is difficult to uniformly form a fine sized through-hole capable of forming a pattern of HD or UHD class.
Alternatively, even though a fine sized through-hole is formed, adjacent through-holes are connected to each other, so that a deposition failure may be generated.
Accordingly, a newly structured substrate for deposition mask, a deposition mask and a manufacturing method thereof are required.